Planning an order of fans or motors from China? Enter the carton size, weight and units per carton and see how many fit in each container type, the CBM, whether you hit the weight limit first, and the FCL vs LCL break-even. Longwell's standard carton sizes are available as presets.
No signup · Works on mobile · Formulas shown below · Updated 2026-08-23
Cartons / Units per Container
Floor-loaded (best-fit orientation) or palletised. Inner dimensions and payloads are typical ISO values; check your carrier.
Results
Engineering estimate for preliminary sizing. Verify against the fan curve, local codes and your system measurements before purchase. Ask a Longwell engineer to check your duty point free of charge.
Container reference data
Container
Inner L × W × H (mm)
Door W × H
Volume
Max payload
Typical usable
20 ft GP (dry)
5,898 × 2,352 × 2,393
2,340 × 2,280
33.2 m³
28.2 t
25–28 m³
40 ft GP
12,032 × 2,352 × 2,393
2,340 × 2,280
67.7 m³
26.5 t
55–60 m³
40 ft HQ (high cube)
12,032 × 2,352 × 2,698
2,340 × 2,585
76.3 m³
26.5 t
65–70 m³
45 ft HQ
13,556 × 2,352 × 2,698
2,340 × 2,585
86 m³
26 t
74–78 m³
ISO 668 / typical carrier values; individual boxes vary by ±20 mm. Road limits at destination (e.g. 20–22 t gross for a 40 ft in many EU/US states) are often lower than the container rating.
CBM = L × W × H ÷ 1,000,000,000 (mm) = L × W × H (m) Cartons = ⌊Lc/l⌋ × ⌊Wc/w⌋ × min(⌊Hc/h⌋, stack limit) — best of 6 orientations × fill efficiency Weight check n × carton kg ≤ payload LCL vs FCL break-even ≈ 12–15 CBM for a 20 GP, ≈ 28–30 CBM for a 40 HQ
Packing fans for export — what Longwell does
Carton sizes are designed to the container: 520/560 mm modules tile a 2,352 mm width (4 × 560 + gap) with minimal waste; this alone is worth 5–8 % more fans per box.
Stacking strength: 5-ply (BC-flute) cartons with corner protectors for 6–8 high; heavy EC plug fans in plywood crates, 3–4 high.
Pallets on request (fumigated ISPM-15 or plastic), shrink-wrapped with edge boards — for warehouses with forklifts only; floor-loading gives 10–15 % more quantity.
Loading plan and photos are sent before departure with the packing list: carton count, net/gross weight, CBM per SKU.
Mixed SKUs: heaviest at floor, matching footprints per column; partial columns filled with accessories (guards, controllers).
Frequently Asked Questions
How many cartons fit in a 40 HQ container?
Divide the inner dimensions (12,032 × 2,352 × 2,698 mm) by the carton dimensions in the best orientation and multiply, then allow 85–92 % for practical loading. A 520 × 520 × 280 mm carton fits about 23 × 4 × 9 = 828 theoretical, ~700–750 in practice.
How do I calculate CBM?
Multiply length × width × height in metres. A 0.52 × 0.52 × 0.28 m carton is 0.0757 CBM; 500 cartons are 37.9 CBM — a 40 ft GP or HQ load.
When is FCL cheaper than LCL?
Roughly above 12–15 CBM, a 20 GP full container costs about the same as LCL freight plus the per-CBM handling charges, and avoids consolidation damage and delays. Above ~28–30 CBM move to a 40 HQ.
What is the weight limit for a 40 ft container?
The ISO payload is about 26.5 t, but road regulations at origin and destination usually limit the gross to 20–24 t. Fans are light (volume-limited); motors and metal-housed blowers can hit the weight limit at 60–70 % volume.
Can Longwell adapt carton sizes to my container plan?
Yes. For OEM volumes we design the carton and units-per-carton around the container module and your warehouse racking, and supply a loading plan with every shipment.
Link to or Cite This Tool
This calculator is free to reference in articles, forums, specifications and course material. Please credit it with a link:
